Artery Stenosis In Hypertensive Patients Research Articles

Triglyceride glucose index is associated with functional coronary artery stenosis in hypertensive patients.

The triglyceride glucose (TyG) index is an effective method for determining insulin resistance (IR). Limited research has explored the connection between the TyG index and functionally significant stenosis in hypertensive patients. Furthermore, the connections between the TyG index, fat attenuation index (FAI) and atherosclerotic plaque characteristics are also worth exploring. The study screened 1622 hypertensive participants without coronary artery disease history who underwent coronary computed tomography angiography. The TyG index was calculated as ln (fasting glucose [mg/dL] * fasting TG [mg/dL]/2). Adverse plaque characteristics (HRPCs), high-risk plaques (HRPs), FAI, and CT-derived fractional flow reserve (FFRCT) were analyzed and measured for all patients. Functionally significant stenosis causing ischemia is defined as FFRCT ≤ 0.80. Two patient groups were created based on the FFRCT: the FFRCT < 0.80 group and the FFRCT > 0.80 group. In hypertensive patients, the association between the TyG index and FFRCT was examined applying a logistic regression model. The TyG index was higher for people with FFRCT ≤ 0.80 contrast to those with FFRCT > 0.80. After controlling for additional confounding factors, the logistic regression model revealed a clear connection between the TyG index and FFRCT ≤ 0.80 (OR = 1.718, 95% CI 1.097-2.690, p = 0.018). The restricted cubic spline analysis displayed a nonlinear connection between the TyG index and FFRCT ≤ 0.80 (p for nonlinear = 0.001). The TyG index increased the fraction of individuals with HRPs and HRPCs, FAI raised, and FFRCT decreased (p < 0.05). The multivariate linear regression analysis illustrated a powerfulcorrelation between high TyG index levels and FAI, FFRCT, positive remodeling (PR), and low-attenuation plaque (LAPs) (standardized regression coefficients: 0.029 [p = 0.007], -0.051 [p < 0.001], 0.029 [p = 0.027], and 0.026 [p = 0.046], separately). In hypertensive patients, the TyG index showed an excellent association with a risk of FFRCT ≤ 0.80. Additionally, the TyG index was also linked to FAI, FFRCT, PR, and LAPs.

Circulating choline is associated with coronary artery stenosis in patients with hypertension: A cross-sectional study of Chinese adults.

Choline is an important nutrient involved in multiple biosynthesis pathways. However, whether circulating choline levels are associated with the risk of hypertension (HTN) and artery stenosis in HTN remains unknown. We investigated the correlations of plasma choline with HTN and coronary artery injury and explored the utility of plasma choline as a diagnostic biomarker for HTN and artery stenosis. 193 HTN patients and 154 age- and sex-matched healthy controls (CON) were recruited in this study. Fasting plasma choline was detected using liquid chromatography tandem mass spectrometry. Choline levels were significantly higher in HTN without artery stenosis (HTN-AS) than CON (8.07 [7.19-9.24] μM vs 7.03 [6.21-8.13] μM, P<.01) group and were further upregulated in HTN with artery stenosis (HTN+AS) (8.63 [7.09-10.59] μM, P<.01) group. Patients with multivessel disease (MVD) also exhibited higher choline levels than those with single vessel disease (SVD) (8.64 [7.16-10.55] μM vs 8.04(6.74-9.38) μM, P<.01). Increased choline levels were independently associated with the risk of HTN (OR=1.2, 95% CI: 1-1.45, P=.05), HTN+AS (OR=1.27, 95% CI: 1.09-1.48, P<.01), and MVD (OR=1.16, 95% CI: 1.02-1.31, P=.02) after adjustment for multiple risk factors. Receiver operating characteristic (ROC) analysis showed that choline had an area under curve (AUC) score of 0.69, 0.67, and 0.63 in determining HTN, HTN+AS, and MVD. In conclusion, higher choline levels were associated with increased risk of HTN and artery stenosis in hypertensive patients.

Lipoprotein (a) as a residual risk factor for atherosclerotic renal artery stenosis in hypertensive patients: a hospital-based cross-sectional study

BackgroundLow-density lipoprotein cholesterol (LDL-c) has been proven to be a risk factor for atherosclerotic cardiovascular disease (CVD), while lipoprotein (a) (Lp(a)) is a residual risk factor for CVD, even though LDL-c is well controlled by statin use. Importantly, the role of Lp(a) in atherosclerotic renal artery stenosis (ARAS) is still unknown.MethodsFor this hospital-based cross-sectional study, patients who simultaneously underwent coronary and renal angiography were examined. ARAS was defined as a 50% reduction in the cross-sectional (two-dimensional plane) area of the renal artery. Data were collected and compared between ARAS and non-ARAS groups, including clinical history and metabolite profiles. Univariate analysis, three tertile LDL-c-based stratified analysis, and multivariate-adjusted logistic analysis were conducted, revealing a correlation between Lp(a) and ARAS.ResultsA total of 170 hypertensive patients were included in this study, 85 with ARAS and 85 with non-RAS. Baseline information indicated comparability between the two groups. In the univariate and multivariate analysis, common risk factors for atherosclerosis were not significantly different. Stratified analysis of LDL-c revealed a significant increase in the incidence of ARAS in patients who had high Lp(a) concentrations at low LDL-c levels (odds ratio (OR): 4.77, 95% confidence interval (CI): 1.04–21.79, P = 0.044). Further logistic analysis with adjusted covariates also confirmed the result, indicating that high Lp(a) levels were independently associated with ARAS (adjusted OR (aOR): 6.14, 95%CI: 1.03–36.47, P = 0.046). This relationship increased with increasing Lp(a) concentration based on a curve fitting graph. These results were not present in the low and intermediate LDL-c-level groups.ConclusionIn hypertensive patients who present low LDL-c, high Lp(a) was significantly associated with atherosclerotic renal artery stenosis and thus is a residual risk factor.

Prevalence and predictors of atherosclerotic renal artery stenosis in hypertensive patients undergoing simultaneous coronary and renal artery angiography; a cross-sectional study.

Introduction: According to the non-specific presentation of atherosclerotic renal artery stenosis (ARAS), this disease is usually an under-diagnosed in clinical conditions. Objectives: The aim of the presence study was to evaluate the prevalence of renal artery stenosis (RAS) and its related risk factors in hypertensive patients undergoing coronary angiography. Patients and Methods: In a cross-sectional study, between March 2009 and October 2010, all of hypertensive patients candidate for diagnostic cardiac catheterization, underwent nonselective renal angiography before completion of their coronary angiography procedure. A standardized questionnaire was used to collect demographics, cardiac history, indications for cardiac catheterization and angiographic data. The degree of ARAS was estimated visually by skilled cardiologist. Narrowing greater than 50% of the arterial lumen considered as arterial stenosis. Data was analyzed by SPSS version 19, and by chi-square test and logistic regression model. Results: In overall 274 patients with mean age of 60.75 ± 10.92 years 108 (39.4%) were male and 166 (60.61%) were female. The prevalence of ARAS calculated 18.2%. According to the present study, heart failure and smoking were predictors of ARAS. However, old age, gender, diabetes mellitus, hyperlipidemia and family history of cardiovascular disease were not clinical predictors of significant ARAS in hypertensive patients, candidate for coronary angiography. Conclusion: According to present data, we suggest to consider renal artery angiography in combination with coronary artery angiography especially in hypertensive patients who are smoker or individuals who have heart failure.

Plasma Lipoprotein(a) Levels and Atherosclerotic Renal Artery Stenosis in Hypertensive Patients

Background/Aims: The contribution of emergent cardiovascular risk factors to atherosclerotic renal artery stenosis (ARAS) is debated. We investigated the relationship of lipoprotein(a) and prothrombotic factors with ARAS in hypertension. Methods: In 50 hypertensive patients with angiographic evidence of ARAS and 58 hypertensive patients who had comparable cardiovascular risk factor burden but no evidence of renovascular disease, we measured renal function, lipoprotein(a), homocysteine, and hemostatic-fibrinolytic markers. Results: Patients with ARAS were more frequently smokers and had longer duration of hypertension, heavier antihypertensive treatment, and worse renal function than controls. Lipoprotein(a) was higher in patients with ARAS than controls, whereas no differences were found in homocysteine and all hemostatic variables. Multivariate analysis showed that lipoprotein(a) was associated with ARAS independent of other confounders including renal function and history of coronary heart, cerebrovascular, and peripheral artery disease. Conclusion: Lipoprotein(a) might contribute to the development of ARAS and detection of elevated levels of this lipoprotein could raise the suspicion of renovascular disease in patients with high blood pressure.

Correlation of ascending aorta elasticity and the severity of coronary artery stenosis in hypertensive patients with coronary heart disease assessed by M-mode and tissue Doppler echocardiography.

The main objective of this study is to investigate the relationship between ascending aorta elasticity and the severity of coronary artery stenosis in essential hypertensive patients with coronary heart disease (CHD) using M-mode and tissue Doppler echocardiography. A total of 184 hypertensive patients with CHD were enrolled. Patients were divided into three groups based on the severity of coronary stenosis measured by coronary arteriography (CAG): slight stenosis (group 1), moderate stenosis (group 2) and serious stenosis (group 3). M-mode and tissue Doppler echocardiography were performed, and elasticity indexes of ascending aorta including stiffness index, distensibility index, and S wave speed of anterior wall were calculated and correlated with the severity of coronary stenosis. Ascending aorta stiffness index was increased, whereas distensibility index and S wave speed of anterior wall were decreased in moderate and severe stenosis groups compared with slight stenosis group (P<0.01). Elasticity indexes change in a stepwise pattern with the narrowness of coronary artery, and there was a significant correlation between aortic elasticity and severity of coronary artery by Pearson correlation analysis (P<0.01). Elasticity indexes of ascending aorta correlate well with severity of coronary stenosis. Elasticity indexes of ascending aorta can serve as predictors for coronary arterial lesion in hypertensive patients.

Frequency and Predictors of Renal Artery Stenosis in Hypertensive Patients Undergoing Coronary Angiography

Renal artery stenosis (RAS) and coronary artery disease share common risk factors. We investigated the frequency and predictors of RAS among hypertensive patients who underwent elective coronary angiography. A total of 832 hypertensive patients underwent coronary and renal angiography at the same session. Renal artery stenosis was classified as mild, moderate, or severe. The study population consisted of 4 groups; 71.1% with normal renal arteries, 12.5% with mild, 8.9% with moderate, and 7.5% with severe RAS. The prevalence of significant (≥50%) RAS was 16.3%. The Gensini score showed a stepwise rise with increasing severity of RAS. Age, duration of hypertension, estimated glomerular filtration rate, Gensini score, and multivessel disease were independent predictors for the presence of RAS. Hypertensive patients with those risk factors might need detailed investigation for RAS which may affect their prognosis.

Research of multiarterial atherosclerotic disease in hypertensive patients with renal artery stenosis

The detection of the renal artery stenosis in hypertensive patients can be a signal of systemic arterial atherosclerosis. To identify and characterize clinical-epidemiologically the hypertensive patients with renal artery stenosis, evaluating factors of cardiovascular risk and presence of symptomatic multiarterial atherosclerotic. Were selected the hypertensive patients who were assisted at the Nephrological Clinic of Universidade Federal do Triângulo Mineiro (UFTM) between 2000-2010, with diagnosis of renal artery stenosis of atherosclerotic etiology. Epidemiological data were evaluated (gender, age, ethnicity), factors of cardiovascular risk (diabetes, hypercholesterolemia, hypertriglyceridemia, tabagism, metabolic syndrome), information on hypertension (time of diagnosis, family report, number of used medicines), previous cardiovascular events (acute myocardial infarctation, ischemic stroke, peripheral arterial disease). Blood pressure levels, global cardiovascular risk and Score Framingham were stratified. Casuistry of 30 patients, feminine majority (73.3%), average of 66 year-old age, 86.67% white, medium time of hypertension of 19.94 years, 89.92 without family report, 13.8 with diabetes, 65.51% smoking, 17.25% hypertriglyredemia, 62.06% with hypercholesterolemia and 66.7% with metabolic syndrome. Average number of medicines in use: 3.26. Dominant right-sided renal artery stenosis separately (46.7%) and in proximal third (56.7%). High creatinine levels in 40% of the patients. As for the hypertension phase, majority phase 2 (47%) and 73.3% with high global cardiovascular risk. Average Framingham Score of 13%. 66.7% presented atherosclerotic disease in another place, being infarctation the main one (53.3%). The most common correlation was with acute myocardial infarctation, what implicates in the search of the coronary compromising to the diagnosis of renal artery stenosis in hypertensive patients to try avoid future damages to the patient.

Reduced Antegrade Flow in the Coronary Sinus Is a Predictor of Coronary Artery Stenosis in Hypertensive Patients

The purpose of this study was to evaluate the feasibility of assessing blood flow in the coronary sinus by transthoracic Doppler echocardiography for detecting coronary artery stenosis in hypertensive patients. Flow in the coronary sinus was studied in 105 participants who all had undergone coronary angiography: 35 nonhypertensive patients, 34 hypertensive patients without coronary artery disease (CAD), and 36 hypertensive patients with CAD. The antegrade phase of flow in the coronary sinus was analyzed and compared among the groups. Multivariate analysis for blood flow and coronary artery stenosis was done. Compared with the nonhypertensive patients, the hypertensive patients without CAD had significantly higher blood flow (9.36 ± 5.94 vs 5.84 ± 2.91 mL/stroke and 584.45 ± 177.32 vs 327.68 ± 125.48 mL/min, respectively; P < .001) in the coronary sinus. Compared with the hypertensive patients without CAD, those with CAD had significantly lower blood flow (5.18 ± 0.72 vs 9.36 ± 5.94 mL/stroke and 352.51 ± 156.18 vs 584.45 ± 177.32 mL/min; P < .001) and a lower velocity time integral (13.14 ± 2.51 vs 19.85 ± 4.89 cm; P < .01). Stepwise multiple regression analysis indicated that the coronary sinus diameter, velocity time integral, and heart rate significantly correlated with the blood flow per minute in the coronary sinus in each group, and the flow per minute was the independent determinant of the percent stenosis diameter. The sensitivity, specificity, and accuracy for the prediction of severe stenosis (>70%) in the left coronary artery were 91.07%, 87.76%, and 88.49% for blood flow of less than 220 mL/min in the coronary sinus. Transthoracic Doppler echocardiography can effectively depict blood flow changes in the coronary sinus, and reduced antegrade flow is a sensitive and specific predictor of coronary artery stenosis in hypertensive patients.

Are Plasma Renin Activity and Aldosterone Levels Useful as a Screening Test to Differentiate Between Unilateral and Bilateral Renal Artery Stenosis in Hypertensive Patients?

Are Plasma Renin Activity and Aldosterone Levels Useful as a Screening Test to Differentiate Between Unilateral and Bilateral Renal Artery Stenosis in Hypertensive Patients?

Are plasma renin activity and aldosterone levels useful as a screening test to differentiate between unilateral and bilateral renal artery stenosis in hypertensive patients?

To evaluate the serum aldosterone (Ald)/plasmatic renin activity (PRA) ratio as a surrogate marker of renin-angiotensin-aldosterone system status in unilateral (Uni)- and bilateral (Bi)-renal artery stenosis (RAS). Seven hundred and eight hypertensive patients (HTP) were studied. Intermediate and high pretest risk of RAS was detected in 66 HTP who subsequently underwent renal gadolinium-enhanced magnetic resonance and arteriography. After application of exclusion criteria 51 HTP remained: 16 with Uni-RAS, 16 with Bi-RAS and 19 essential hypertensives with normal arteries. Nineteen normotensive individuals were also studied. Ald and PRA were determined before and after stenosis resolution by balloon angioplasty and stent implantation. Ald/PRA (ng/dl per (ng/ml per h(-1))) was markedly high in Bi-RAS (5.92 +/- 2.30, P < 0.001), and markedly low in Uni-RAS (0.38 +/- 0.17, P < 0.001) versus essential hypertensives (1.52 +/- 2.02). Multilevel likelihood ratios for Bi-RAS were positive for Ald/PRA higher than 3.6, negative for Ald/PRA lower than 0.2, and neutral for Ald/PRA at least 0.2 and 3.6 or less. ROC analysis identified Ald/PRA lower than 0.5 and Ald/PRA higher than 3.7 to have the best sensitivity and specificity to detect Uni-RAS and Bi-RAS, respectively. In Uni-RAS, but not in Bi-RAS, postinterventional PRA was significantly lower than basal PRA. In Uni-RAS and Bi-RAS, postinterventional Ald was approximately 30% and approximately three times lower than basal Ald, respectively. In essential hypertensives, PRA and Ald showed no changes in the same period. In the population studied, Ald, PRA and Ald/PRA were significantly different among essential hypertensives, and HTP with Uni-RAS or Bi-RAS. Studies with a higher number of patients will allow exploration of the usefulness of pharmacologic aldosterone blockade in Bi-RAS, and to assess the relevance of Ald/PRA to differentiate Uni-RAS from Bi-RAS.

Are plasma renin activity and aldosterone levels useful as a screening test to differentiate between unilateral and bilateral renal artery stenosis in hypertensive patients?

Are plasma renin activity and aldosterone levels useful as a screening test to differentiate between unilateral and bilateral renal artery stenosis in hypertensive patients?

Prevalence and predictors of renal artery stenosis in hypertensive patients undergoing coronary angiography

Renal artery stenosis (RAS) is a major comorbid condition in patients with coronary artery disease (CAD). Although the reported prevalence of significant RAS among patients undergoing coronary angiography varies from 6.2 to 28% in Western countries, little information is available on the prevalence and predictors of RAS in Middle Eastern countries. From April 2007 to May 2008, 732 hypertensive patients with suspected CAD immediately after selective coronary angiography underwent abdominal aortography with or without selective renal angiography. Coronary angiography revealed stenosis of > or =50% in at least one of the main coronary vessels in 434 (59.3%) patients, including 100 (13.7%) cases with single-vessel CAD, 114 (15.6%) with two-vessel CAD and 220 (30.1%) with three-vessel CAD. Significant RAS was present in 87 patients (11.9%), severe (> or =75%) RAS in 35 patients (4.8%) and bilateral RAS in 37 patients (5.1%). Higher serum creatinine level, severity of CAD, history of coronary artery bypass graft surgery (CABG), congestive heart failure, and pulmonary edema together with atrial fibrillation were the most powerful predictors of significant RAS. In multivariate logistic regression analysis, three-vessel CAD (odds ratio 1.61, 95% confidence interval (1.36-1.91), P<0.001), history of CABG (odds ratio 4.40, 95% confidence interval (1.17-16.5), P=0.028) and serum creatinine level of >1.2 mg per 100 ml (odds ratio 2.12, 95% confidence interval (1.09-4.12), P=0.026) were the most powerful predictors of significant RAS. The prevalence of RAS in our patients was similar to that reported in the Western countries. The presence of multi-vessel CAD or a history of CABG along with a higher serum creatinine level in hypertensive patients undergoing coronary angiography was found to be a risk factor for RAS.

Prevalence and Predictors of Renal Artery Stenosis in Hypertensive Patients Undergoing Elective Coronary Procedures

This study explored the prevalence and predictors of renal artery stenosis in a cohort of 525 hypertensive patients referred for elective coronary procedures. Patients underwent coronary and renal arteriography. The study defined renal artery stenosis as > or =60% luminal obstruction (physiologic or hemodynamic significance was not tested). Patients were classified into groups of those with normal renal arteries, those with insignificant renal artery stenosis, and individuals with significant renal artery stenosis. The mean age was 52.6+/-8.5 years, and 403 (76.8%) were males. Significant renal artery stenosis was found in 3.6%. It correlated significantly with hypertension duration (P=.005), history of cerebrovascular stroke (P=.01), history of angioplasty to >1 coronary vessel (P=.003), and 3-vessel coronary disease (P=.0003). Multivariate regression analysis identified 2-vessel and 3-vessel coronary artery disease as independent predictors of renal artery stenosis, with odds ratios of 4.9 and 12.1, respectively. It was concluded that invasive screening for renal artery stenosis was probably warranted only in hypertensive patients with multivessel coronary disease referred for elective coronary procedures.

Renal artery stenosis in hypertensive patients with antiphospholipid (Hughes) syndrome: outcome following anticoagulation

We have demonstrated a point prevalence of 26% renal artery stenosis in patients with antiphospholipid syndrome (APS) and uncontrolled hypertension. We describe the effect of anticoagulation on blood pressure control and renal function. We studied 23 patients retrospectively with renal artery stenosis (RAS). Fourteen received oral anticoagulation for more than 1 yr (target International Normalized Ratio (INR) of 3.0-4.5). Five patients had primary APS. Patients were divided into two groups based on their INR (< 3.0 and > or = 3.0). Nine patients had repeat magnetic resonance angiography (MRA) or an angiogram of the renal arteries after 2 yr. Only 8/14 patients managed to maintain their INR > or = 3.0 (median INR 3.1, range 2.8-3.7) while six had a INR < 3.0 (median INR 1.9, range 1.2-2.4). Patients with a median INR < 3.0 had poorly controlled blood pressure and there was significant deterioration in mean serum creatinine values (Wilcoxon's test, P < 0.03). Nine patients underwent follow-up renal artery imaging. Three of nine patients with an INR < 3.0 (median INR 1.9) had re-stenosis and a fourth developed bilateral renal artery stenosis. Five patients with INR > or = 3.0 (median INR 3.1) did not show re-stenosis of the renal arteries; their renal function was stable and blood pressure was well controlled. One other patient with secondary APS (mixed connective tissue disorder) with INR > 3.0 showed recanalization of the stenosed renal artery. Anticoagulation with INR maintained > or = 3.0 helped to control the blood pressure and prevent the progression of renal disease.

Accuracy of Computed Tomographic Angiography and Magnetic Resonance Angiography for Diagnosing Renal Artery Stenosis

Timely, accurate detection of renal artery stenosis is important because this disorder may be a potentially curable cause of hypertension and renal impairment. To determine the validity of computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) compared with digital subtraction angiography (DSA) for detection of renal artery stenosis. Prospective multicenter comparative study conducted from 1998 to 2001. Two panels of 3 observers judged CTA and MRA image data and were blinded to all other results. Digital subtraction angiography images were evaluated by consensus. 3 large teaching hospitals and 3 university hospitals in the Netherlands. 402 hypertensive patients with suspected renal artery stenosis were included. A group of 356 patients who underwent all 3 diagnostic tests was used for analysis. Reproducibility was assessed by calculating interobserver agreement. Diagnostic performance was evaluated in terms of sensitivity, specificity, and other diagnostic variables. Atherosclerotic stenoses of 50% or greater and fibromuscular dysplasia were considered clinically relevant. Twenty percent of patients who underwent all 3 tests had clinically relevant renal artery stenosis. Moderate interobserver agreement was found, with kappa values ranging from 0.59 to 0.64 for CTA and 0.40 to 0.51 for MRA. The combined sensitivity and specificity were 64% (95% CI, 55% to 73%) and 92% (CI, 90% to 95%) for CTA and 62% (CI, 54% to 71%) and 84% (CI, 81% to 87%) for MRA. Eighteen percent of the patients were included nonconsecutively. Digital subtraction angiography may be an imperfect reference test. Computed tomographic angiography and MRA are not reproducible or sensitive enough to rule out renal artery stenosis in hypertensive patients. Therefore, DSA remains the diagnostic method of choice. *For a list of the other investigators and research coordinators who participated in RADISH, see the Appendix.

Changes in renal blood flow reserve after angioplasty of renal artery stenosis in hypertensive patients

Intra-arterial Doppler is a recent technique which allows assessment of distal vascular disease using measurements of intrarenal blood flow velocities. The purpose of this study was to evaluate intrarenal hemodynamics and renal blood flow reserve before and after percutaneous transluminal angioplasty (PTA) in hypertensive patients with unilateral atherosclerotic renal artery stenosis using intra-arterial Doppler. Intra-arterial Doppler was performed during arteriography in 19 hypertensive patients (12 men; mean age, 64 +/- 8 years) in "normal" and in "stenotic" kidneys at baseline, on isosorbide dinitrate, and after selective intra-renal papaverine injection, before, and after PTA. Doppler parameters analyzed were average peak velocity, maximum peak velocity, end diastolic velocity, and renal blood flow (RBF). Changes in Doppler parameters after papaverine injection were also analyzed. The major results were (1) the significant reduction in RBF distal to the stenosis, (2) the lack of arteriolar reactivity in response to papaverine distal to the stenosis, (3) the immediate recovery of arteriolar reactivity after PTA, associated with restoration of RBF in the revascularized kidneys, and (4) no change in arteriolar reactivity in response to papaverine in the "normal" kidneys following PTA. Ours results highlighted the benefit of endovascular Doppler to evaluate (1) RBF reserve, and (2) the repercussion of the stenosis on the distal vascularization.

Comparison of Steerable Continuous-Wave Versus Pulsed-Wave Doppler Ultrasonography to Renal Artery Angiography in Diagnosing Renal Artery Stenosis

Pulsed-wave Doppler ultrasonography is widely used to noninvasively diagnose renal artery stenosis. The use of steerable continuous-wave Doppler has never been tested. We compared pulsed and steerable continuous-wave Doppler ultrasonography, demonstrating that although both methods are highly sensitive for severe stenoses, continuous-wave Doppler shows a better sensitivity for mild to moderate stenoses.

Diagnosis of renovascular disease by intra- and extrarenal Doppler scanning

The purpose of this prospective, angiographically controlled study was to determine the diagnostic value of color Doppler sonography with two differing approaches of scanning in patients with clinical clues for renal artery stenosis (RAS). In 135 hypertensive patients peak systolic velocity in the main renal arteries and the resistive index (RI) of the intrarenal arteries were measured. The RI side-to-side-difference (delta RI) greater than 0.05 or peak systolic velocity greater than 2 m/s were used to discriminate normal from stenotic renal arteries, defined as angiographically confirmed RAS > 50%. In 88 of 135 patients 107 RAS were demonstrated by selective arteriography. Five renal artery occlusions occurred, which were all diagnosed by color Doppler sonography. Seventy-six RAS were detected by increased peak systolic velocity, and an additional 19 stenoses were identified by delta RI. The combined analysis of peak systolic velocity and delta RI resulted in a sensitivity of 89% and specificity of 92%. The positive predictive value was 92% and the negative predictive value was 88%. Our data suggest that only the combination of intra- and extrarenal scanning with color Doppler sonography represents an effective screening method for significant renal artery stenosis in hypertensive patients.

1. Diagnosis of renal artery stenosis in hypertensive patients with colour duplex ultrasound and 131I-hippuran renography

Departments of 1Clinical Physiology and 2Nephrology, Sahlgrenska University Hospital, Göteborg, Sweden'